In the cation of the title salt [systematic name: 4-(2H-1,3-benzodioxol-5-ylmethyl)piperazin-1-ium 2,4,6-trinitrophenolate], C12H17N2O2+·C6H2N3O7−, the piperazine ring adopts a slightly disordered chair conformation. The piperonyl ring system and the piperazine ring are twisted with respect to each other with an N—C—C—C torsion angle of 40.7 (2)°. In the anion, the dihedral angles between the mean planes of the nitro substituents ortho to the phenolate O atom and the mean plane of the phenyl ring are 28.8 (9) and 32.2 (8)°. In contrast, the nitro group in the para position lies much closer to the aromatic ring plane, subtending a dihedral angle of 3.0 (1)°. In the crystal, the cations and anions interact through N—H⋯O hydrogen bonds and a weak C—H⋯O interaction. Weak C—H⋯O interactions are also observed between the anions, forming R22(10) graph-set ring motifs. In addition, a weak centroid–centroid π–π stacking interaction between the aromatic rings of the cation and the anion, with an intercentroid distance of 3.7471 (9) Å, contributes to the crystal packing, resulting in a two-dimensional network along (10-1).